The present invention relates to a coordinate determining device using an electromotive voltage induced by an alternating magnetic field, and more particularly to a coordinate determining device provided with an arithmetic control unit which compensates for an error caused by the inclination of a coordinate indicator.
In the conventional coordinate determining device, a coordinate indicator which generates an alternating magnetic field is positioned adjacent sensing lines and the position of the coordinate indicator on a tablet is computed by using the ratio of a difference between the maximum value of induced signals generated in a plurality of the sensing lines installed on the tablet spaced from each other and each of the induced signals of the sensing lines neighboring the sensing line in which the maximum value of the induced signal is generated. However, in the above mentioned type of device, the computed position is different from the actually indicated position if the pen-shaped coordinate indicator is inclined relative to the tablet.